Meet Zara and Iron Mike, a very unconventional royal couple

She is a brisk sort of girl, and a great believer in just gritting her teeth and getting on with things. But this weekend, as she prepares to compete in an eventing World Cup qualifier in France, Zara Phillips is beset by crises.

Firstly, her beloved and extraordinary horse Toytown has a bruised foot and has had to be pulled out of the competition. Given his age - he is 15 - and that the Beijing Olympics are looming, it is not at all the preparation she was hoping for.

She has trained him with infinite care, and yet she still faces her worst fear - that he will be injured, as he was before the Athens Olympics four years ago. This weekend she is competing in Fontainebleau with two of her other horses instead.

The second crisis - and although she is "deeply" in love it is only a secondary priority - is that her lover Mike Tindall faces disqualification from driving after failing a roadside breath test.

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Zara and her boyfriend, Mike Tindall. The couple are planning to start a family.

Tindall, 29, a rugby player who was one of England's World Cupwinners in 2003, was found to be over the limit a day after a champagne-soaked party at the Cheltenham Gold Cup.

He and Zara went to the private Weighing In Party for jockeys following the racing. It was evidently an extremely jolly affair - some fellow drinkers in Monty's Brasserie in Cheltenham say they saw Tindall, a 16-stone giant of a man, vomiting.

There are reports that his royal girlfriend was so giddy in the convivial atmosphere that she fell off a chair and banged her head.

At around 11am the following day Tindall was stopped in his silver Range Rover and gave a positive breath test. He was arrested and taken to Newbury police station, where he gave a blood test which has been sent for analysis. The results are due at the end of the month.

On the face of it this is a pretty dismaying way for a professional sportsman to behave. No one begrudges a rugby player a bit of a celebration, and of course there is - or was - a great drinking culture in the game, but to be found over the limit well into the following day suggests serious excess.

It's all the more disappointing as Tindall is working his way back to fitness following a horrific injury to his liver which was seriously damaged in a freak accident six weeks ago when he was playing against Wales.

So has Tindall, affectionately known as Iron Mike, been led astray by Zara, 12th in line to the throne but with "a wild streak a mile wide"? And are these two very successful sports people endangering their respective careers with an alcohol-soaked lifestyle?

If you believe family friends and professional associates,what happened at Cheltenham is not --representative of the life the couple lead together.

Although as yet unmarried, they are very much a steady couple,a "Mr and Mrs" in all but name who are deeply committed to a cosy coupledom which embraces long country walks and hearty pub suppers.

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Has Mike been led astray by Zara who has a 'wild streak'?

They are very deeply in love according to everyone who knows them,and Tindall has spoken touchingly of being "head over heels" with Zara.

"It's an incredibly passionate relationship and there are times when she can't keep her hands off him, or he off her," says a local source.

"Not that long ago they were in a racing enclosure with the Queen and Zara was patting his bottom - and he seemed to think that it was completely normal to be fondled like that."

A royal insider concurs. "I can tell you that they are very,very happy together. It seems to be bliss all the way for those two.They both say it is the real thing and the expectation is that they will get married and start a family when the Olympics are over."

Indeed, a couple of months ago there were rumours that Zara was already expecting a baby. It turned out to be a false alarm, but in truth the couple are indeed planning to start a family.

Tindall would like to be married first - anything less would rather appal his mother, and he holds her opinions in high regard.

He has even talked about giving up his own career, which is coming towards its end, to care for the children while she continues her equestrian adventures.

Those close to Zara indicate that she doesn't give a hoot whether she is married or not when babies come along.

This is typical of Zara, who scandalised the establishment by affecting a pierced tongue in her youth.

But she has settled down a great deal under the influence of Tindall, a kindly, upright man from middle-class Yorkshire stock.Tindall's father Philip is a banker and his mother Linda a social worker.

These days Zara loves to cook for her boyfriend - hearty,meaty fare - and takes genuine pleasure in supporting him in a traditional wifely role.

It's all a far cry from the racy pub-and-club lifestyle she indulged in with her former fiancé, the jockey Richard Johnson.

For almost three years now, Zara and Tindall have been living together in a two-bedroomed, Cotswold-stone cottage on the Gatcombe estate near Stroud in Gloucestershire, home to Zara's mother Princess Anne.

The decor has all been picked out by Zara and, barring his video games, it's a pad which looks rather more her taste than his.

Tindall jokingly calls her Monica after the obsessively-tidy character in the TV series Friends. Zara says: "I do go into cleaning frenzies where Mike calls me Monica because I start chucking everything out. So he gets out of the house."

Creating continuous chaos amid this order are their three dogs: a boxer called Sway, who was a birthday present from Mike to Zara, Corley, who is a black Labrador and gun dog, and Misty, an immense bull mastiff who is Tindall's dog. They are both regularly seen out walking the dogs.

Zara is also often spotted zooming around the estate on her mountain bike, which keeps her in phenomenal physical shape.

"Zara has no airs," says a source. "Not long ago I saw her pottering about in her jodhpurs and a pair of Union Jack socks."

Zara is regularly seen at the Waitrose in Stroud, and she also shops at Tesco in nearby Elsworth. On special occasions they go out to Bath or Cheltenham.

She likes the shops in both, and this is where she picks up her "bits and pieces": fedora hats, tight trousers, patent leather belts, oversized gold hoop earrings and splashes of animal print. She has a bracingly vulgar fashion sense, and shows off her generous bosom to devastating effect.

"She was at a ball with Mike in a low-cut dress and his eyes were on stalks all night," reports an observer.

On nights in they watch CSI and Strictly Come Dancing.

When they go out they are regulars at the White Horse in the nearby village of Frampton Mansell. Tindall tends to drink bottled Peroni beer, while Zara enjoys her white wine.

They are familiar faces at the Tunnel House Inn in Tetbury, too. Tindall books in under an assumed name and the couple tend to just have a quiet meal.

This is the pub where Zara famously partied with Prince William and Guy Pelly in 2006. At one point that evening, Zara was seen pretending to pour vinegar into the open fly of a customer who was lying drunk on the floor.

"She was legless that night," says a local. "She can be quite wild, she's got that streak in her."

But such excesses seem to be rare these days, and Tindall's influence can be detected here.

He has revolutionised her training - indeed friends say he is the man who has helped her become the world champion she now is.

Zara, who keeps ten horses, can often be riding for six or seven hours a day. She is at the stables by

7.30am, and works formidably hard.

She has even taken her HGV driving licence so she can drive her horse boxes to competitions. Tindall trains hard with his rugby club, Gloucester, and also exercises at home: he runs, pumps weights, and plays golf.

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A friend on the rugby circuit says of Tindall: "He is very respectable and down to earth. I would not have associated him with heavy boozing - he is not a part of that culture.

"I am sure he is known to indulge from time to time but this is the first time I have heard of him being out of line."

Tindall's account of his alcohol consumption is modest. He said in an interview: "After the match I'll have a couple of pints with the lads.

"The pies-and-pints culture in rugby has changed and I barely drink any alcohol during the week, maybe a glass of wine, but there's nothing wrong with a few beers after a match."

Tindall has only recently signed a three-year, £600,000contract with Gloucester, and he and Zara have a string of commercial deals and sponsorships.

Tindall was an ambassador for Guinness and for a brand of watches. Zara has a deal with Chivas, with Rolex, with Land Rover and with a brand of horse joint supplement called Cortaflex.

Her income has been estimated at around £250,000 a year, butthe cost of keeping the horses alone is said to run at around £500,000.

She is free to take on such endorsements because Princess Anne rejected the HRH title for her and her brother Peter - which means she can freely milk her status commercially without permission from the Queen.

What she desires most though is in its own way a continuation of family tradition: to compete successfully at the Olympics.

Her father won an eventing team gold medal at the Munich Olympic Games in 1972 and a team silver medal at the Seoul Olympics 16 years later. Her mother also represented Britain at the 1976 Games in Montreal.

Zara, who has already won the World and European eventing titles, says: "Everyone compares us, but we're from totally different eras. But it would be good to win some Olympic medals as well."

Her friends talk of tunnel vision setting in when it comes to the Olympics. "Zara is completely focused on coming home with a gold medal," says a royal source.

The only slight distraction will be her duties as a brides maid at her brother Peter's wedding in May at Windsor Castle - and one imagines any court case which might arise from Tindall's alleged drink-driving.